[meteorite-list] Active Volcanoes Revealed on Venus

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Tue, 18 Mar 2014 14:42:10 -0700 (PDT)
Message-ID: <201403182142.s2ILgApG029311_at_zagami.jpl.nasa.gov>

http://news.discovery.com/space/active-volcanoes-revealed-on-venus-140317.htm

Active Volcanoes Revealed on Venus
Irene Klotz
Discovery News
March 17, 2014

Scientists have long suspected that volcanoes played a huge role in the
evolution of cloud-shrouded Venus, the second planet from the sun.

Now, images from Europe's Venus Express orbiter are showing that volcanic
eruptions may not just be a thing from the past.

Scientists discovered four transient bright spots in a relatively young
rift zone known as Ganiki Chasma, which was observed 36 times by the spacecraft's
Venus Monitoring Camera.

"Venus might have ongoing volcanism," planetary scientist Alexander Bazilevskiy,
with the Max-Planck Institute for Solar System Research in Germany, said
at the Lunar and Planetary Science Conference in Houston on Monday.

Bazilevskiy and colleagues constructed mosaics from images taken during
the orbital passes and computed the relative surface brightness.

They found four transient flashes, estimated to be between 980 degrees
and 1,520 degrees Fahrenheit - well above the planet's normal 800 degree
Fahrenheit surface temperature.

The Metallic Snows of Venus

"We were looking for these spots for several years (and) didn't find,"
anything, Bazilevskiy said.

He and colleagues figured the chance of seeing anything was extremely
slim, just about 8 percent.

"Then we found something," Bazilevskiy said.

Four places, actually, all near Maat Mons, a giant shield volcano on Venus
that scientists believe last erupted 10 million to 20 million years ago.

"Geologically, it's like yesterday," Bazilevskiy said.

Follow-up analysis suggests the bright flashes could be lava flows stretching
16 miles or so, a chain of cinder cones, or a volcanic hotspot similar
to what has been found on Jupiter's volcanically active moon Io.

Scientists plan to comb through archived radar images of Venus made with
NASA's Magellan spacecraft between 1990 and 1994 to see if they can find
any other evidence of potential volcanic activity.

The team also is continuing to use the eight-year-old Venus Express spacecraft
to look for flashes in other rift zones.

In a synopsis of the research, lead author Eugene Shalygin, also with
the Max-Planck Institute, wrote that the discovery of present-day volcanic
activity on Venus would have "major implications" for understanding processes
in the planet's interior, surface and atmosphere.
Received on Tue 18 Mar 2014 05:42:10 PM PDT